Maybe its just a testament to how good pCARS is that it can be hard to tell sometimes, but the 5th one down is a real picture (its a reference picture of the Formula Gulf, which was included in some of the press materials when licensing was announced so people knew what they were getting.)

Alejandro Gorgal

Good point, also worth noting: all other pictures were taken by the community, not the developers, so there’s no trickery here.